Condensing means for an internal combustion engine



Dec. 10, 1 935. R. s. WENTWORTH CONDENSING MEANS FOR AN INTERNAL COMBUSTION ENGINE 2 Sheets-Sheet 1 Filed Dec. 6, 1933 Dec. 10, 1935. R. s. WENTWORTH CONDENSING MEANS FOR AN INTERNAL COMBUSTION ENGINE Filed Dec. 6, 1933 2 Sheets-Sheet 2 ROBERT S. WAT/WWO)?! Patented Dec. 10, 1935 UNITED STATES PATENT OFFICE CONDENSING MEANS FOR AN INTERNAL COMBUSTION ENGINE Application December 6, 1933, Serial No. 701,206

9 Claims.

This invention relates to improvements in the cooling system of an internal combustion engine. More especially it has to do with improved apparatus for preventing wastage of an anti-freez- 5 ing solution and for insuring the user that such solution will continue to be effective to the extent desired.

It is generally recognized that alcohol is one of the most desirable anti-freeze agents to be add- 10 ed to the water in the cooling system of an internal combustion engine. It mixes thoroughly with the water, does not alter its consistency appreciably and has no damaging effect on the metal or rubber parts with which it comes in 15 contact. It is furthermore not liable to solidify or take a crystalline form at any temperature encountered in the ordinary use of vehicles such as aeroplanes, automobiles, motor boats, and the like. But-and this is a vital defect of alcohol 20 as ordinarily usedit is well known that at normal operative temperatures alcohol will pass out of solution and become vaporized. If the system is vented to atmosphere, as it usually is and as it always should be for safety, the vaporized alco- 25 hol escapes with a characteristic odordeemed by most persons to be distinctly offensive. The loss of this alcohol by evaporation not only reduces the quantity of the cooling solution as a whole but what remains has a less percentage of alcohol 30 than the original solution and so is not capable withstanding the low temperature for which the original filling was intended. This ever present danger of vaporization has led to the development of several other anti-freeze solutions hav- 35 a higher boiling point. While some of these have proved successful, they are without excepticn considerably more expensive than alcohol and have no appreciable advantage thereover except that they are usually odorless and are not subject to vaporization at temperatures ordinarily encountered use.

Moreover, regardless of whether alcohol or one of the numerous other anti-freeze agents is employed the user of the engine almost invariably l fills his cooling system while it is at normal atmospheric temperature. As a result when the engine is started and continues to run for any appreciable period the solution becomes heated and expands. This causes it to boil over or be 50 wasted through the vent pipe of the system. This in and of itself is not so harmful or dangerous but it leads to the opportunity for later adding just ordinary water to the cooling system to fill the radiator. It is quite the custom in most 55 public garages to so fill the radiators of all automobiles stored there overnight and it is common knowledge that when anyone stops at a filling station for fuel or oil the attendant is most apt to see how your water is and, if the radiator is not full, to add water to the cooling system. After 5 such additions of water, whether in the overnight garage, at the filling station, or by the user of the vehicle himself, another expansion follows with further wastage of the cooling solution. Part of this lost liquid is the anti-freeze constituent and so in this way the solution as a whole is slowly deteriorated and in time, quite frequently before the user ever realizes it, his cooling liquid has lost its effectiveness as a true anti-freeze solution for several degrees above that which he feels he can encounter with safety.

It is an object of the present invention to provide apparatus so constructed and arranged that alcohol in particular, or any other anti-freeze liquid as well can be used with safety. It is an object to provide for the reception and retention of that portion of the solution which has heretofore been lost as a result of the expansion of the liquids when heated. It is a further object to provide for the entrapping of the vapor of the alcohol or other anti-freeze agent and retain it long enough for it to be transformed again to a liquid. Involved in this is the object of providing heat transfer means for aiding the absorption of the heat from the vapor. It is a feature that when the internal combustion engine cools down with resulting shrinkage of the cooling solution in the cooling system proper, the solution retained in the apparatus of the invention will be drawn over into the radiator to maintain the system properly filled at all times. Other features reside in certain details of construction which will be appreciated as the description develops.

The best mode in which I have contemplated applying the. principles of my invention is shown in the accompanying drawings, but these are to be taken as merely illustrative because it is intended that the patent shall cover by suitable expression in the appended claims whatever features of patentable novelty exist in the invention as a whole.

In the accompanying drawings:

Figure 1 is a side elevation, somewhat diagrammatic, showing how apparatus embodying the invention may be applied in different locations on an automobile;

Figure 2 is a median vertical section (as on line 2--2 of Figure 4) through one form of accumulation chamber and a novel condenser therein;

Figure 3 is another median section taken as on line 3-3 of Figure 4;

Figure 4 is a plan in section on line 44 of Figure 2;

Figure 5 is a vertical section through a portion of a modified form of accumulation chamber;

Figure 6 is a median vertical section, as on line 66 of Figure '7 showing a modified form of condenser and base;

Figure '7 is a plan in section as on line 1-1 of Figure 6;

Figure 8 is a median vertical section, as on line 8--8, of Figure 9, showing further modifications;

Figure 9 is a plan in section as on line 9-9 of Figure 8;

Figure 10 is an elevation of a safety detail; and

Figure 11 is a plan in section on line H-l I of Figure 10.

Referring now more particularly to the drawings the conventional illustration of Figure 1 shows an internal combustion engine I!) with a radiator l2 connected thereto by the conduit l4 at the top and another conduit 16 at the bottom in which may be included a circulating pump I8. The space in the water jacket about the engine and in the radiator contains a liquid which absorbs heat from the engine and passes thence through conduit 14 into the radiator where heat is extracted as the liquid flows downward. The

cooled liquid again enters the water jacket through conduit l6 and the cycle is repeated. If the system is initially filled with liquid at atmospheric temperature, when it is heated up by the running of the engine the liquid expands and part of it flows out of an overflow tube 20 connected to the radiator at the top near the filler cap 22. Ordinarily this tube 20 extends down below the engine where the overflow can fall to the ground. If the cooling liquid is an antifreeze solution intended to remain liquid down to some predetermined temperature, the loss of part of this liquid during the aforesaid overflow paves the way for a replenishing of the system with water. When this is done the solution as a whole is diluted and its freezing point is thereby raised. It not infrequently happens that repeated overflows and repeated refillings with water so greatly dilute the solution that the latter is unable to remain liquid at the ordinary temperatures encountered in winter weather. Moreover if the solution has an ingredient such as alcohol for the antifreeze agent this may be vaporized during the operation of the engine and escape through the overflow pipe. The growing practice of equipping vehicles with so-called hot water heaters increases the liability of losing the cooling solution. When such heaters are installed it is customary to provide thermostatic valves in the conduit l4 between the engine jacket and the radiator and to set these valves so as to restrict flow until the temperature of the cooling solution is in the neighborhood of 160 F. This enforced heating up of the solution not only results in greater loss by expansion of the liquid but also tends to a greater loss by way of evaporation. When such loss occurs it is obvious that if the radiator is refilled with plain water the proportion of water to alcohol or other anti-freeze agent is increased and the effectiveness of the solution to withstand freezing temperature is correspondingly reduced.

The present invention provides means to entrap both the liquid overflow and the vapor that may pass into the tube 20. This means is a tank or accumulation chamber having fluid communication with the tube 20 and thus with the high point of the cooling system proper. The accumulation chamber may be of any convenient form. In Figure 1 two such forms are shown, one of which is a cylindrical container 24 adapted to be mounted on the engine side of the dash 26, and the other of which is a tank 28 of appreciable horizontal extent adapted to be fastened to the floor-board 30 or underside of the vehicle. The exact location of the chamber is not material, if placed under the hood on the dash it is bathed by the air blast from the fan 32, whereas if placed underneath the vehicle it is exposed to the colder air of the outside atmosphere. The form of chamber selected may be determined by the capacity of the cooling system and the accessibility of its place of attachment.

The cylindrical form of chamber is conveniently provided by a tubular barrel 24 secured between a base 34 and a cover 36. As here shown this barrel may be made of sheet metal with a lapped seam and the base and cover may be made of malleable castings. The horizontal tank 28 may be of sheet metal or cast and preferably has a depending sump 28 such as shown in Figure 5. In any case the chamber is connected to the overflow tube 20 by a suitable conduit 38 and it is important that the outlet of this connection be somewhat above the bottom of the accumulation chamber and so located therein that an inverted cup-shaped element, hereinafter termed a bell, can be placed with its dome and skirt overlying the said outlet. As illustrated in the drawings the conduit 38 is connected to a hole 40 in the bottom of the base of the accumulation chamber. In Figure 5 the sump 28 comprises the base 36'. In Figures 2 to '7 the base is shown as having upstanding on its inner surface a cylindrical wall 42 around the said hole 40. The opening 42' at the upper end of this wall is deemed to be the inlet opening to the accumulation chamber or, perhaps more specifically, the outlet of the fluid connection between the accumulation chamber and the cooling system proper. In Figures 8 and 9 the base is shown as having a raised hub 44 on its inner face into which a pipe 46 is fitted so as to stand upright in the accumulation chamber. Near its upper end this pipe has the greater part of its wall cut away to provide openings 46 into the accumulation chamber. This, again, is deemed to be the outlet of the fluid connection between the said chamber and the cooling system proper.

As previously suggested a bell 50 is placed with its dome 52 and skirt 54 overlying the outlet of the connection with the cooling system proper. In Figures 2 to '7 inclusive this bell is shown as made of malleable casting and as being mounted on the base of the accumulation chamber. In Figures 2 to 5 the base 34 (3.4) is provided with lugs 55 upon which the bottom edge of the bell rests and with other lugs 58 adapted to be peened over onto suitable outstanding projections 66 on the bell to secure the latter to the base. In Figures 6 and '7 the bell 50A rests on upstanding fins 62 cast integral with the base 34A and is held thereon by the engagement of peenable lugs 58 on the base with projections on the lower edge of the bell skirt 54A. In Figures 8 and. 9 the bell 58B is shown as made of sheet metal with a dome 52B and a skirt 543 secured tightly together. The dome is provided with a hole 64 to receive a fitting 65 which fits on the upper end of pipe 6 above its openings 46'. It is obvious that the bell maybe mounted in other ways in the accumulation chamber, but it is essential that the outlet of the fluid connection between this chamber and the cooling system proper shall be beneath. the bell.

At one side of the base is an opening 12 in which an open tube 14 upstands within the chamber to near the top thereof, and another tube 16 leads externally therefrom to a location where drainage can fall conveniently. The skirt of the bells 50 and 50A may be suitably shaped as at 5 and 54A respectively to accommodate the upstanding tube 14. One purpose of this vent to atmosphere is to permit the level of liquid in the chamber to rise and fall under atmospheric pressure.

When the cooling system is first filled with liquid, for example, a solution of water and alcohol, some of it may overflow into the tube 20 and thence flow through conduit 38 into the accumulation chamber. Indeed, it may be preferred to add sufficient solution to the system to insure that the liquid will stand in the chamber above the lower edge of the bell thus sealing the space within the bell from the space outside thereof in the chamber. But this Dre-sealing is not deemed essential because in the operation of the system this sealing is automatically cared for. When the engine is started and the solution heats up and expands, the usual resulting overflow into tube 20 passes into the conduit 38 and thence to the accumulation chamber. Thus the apparatus of the invention provides for the entrapping of the overflow consequent upon the expansion of the cooling solution. The extent to which this occurs is of course dependent upon the capacity of the system and the temperature of the solution. No specific limits or regulations need be stressed, except that prior to any evaporation of the cooling solution the liquid in the accumulation chamber should stand above the lower edge of the bell and thus provide a liquid seal for the space within the bell. It is not at all objectionable if the level of the solution in the chamber outside the bell is entirely above the latter.

It has been noticed in studying the vaporization which occurs in the cooling system of an internal combustion engine that the normal vaporization is not a. steady or uniformly progressive action but on the contrary occurs with considerable irregularity. That is, there may be a very appreciable amount of vaporization for a short period followed by a definite pause before the succeeding evaporation occurs. Advantage is taken of this fact in the present apparatus by providing for the entrapping of the vapor as it passes to the accumulation chamber during a period of vaporization and then effecting the transfer of heat from this entrapped vapor, during the subsequent pause, to condense the vapor back to liquid.

When the liquid rises in the accumulation chamber above the lower edge of the bell, air is entrapped within the bell above it. Also air initially in the solution may come out and reach the space within the bell and when the liquid in the accumulation chamber is drawn back into the cooling system proper to the extent that the liquid seal around the mouth of the bell is broken, air will then enter the bell. While the presence of this air is not entirely objectionable it is desirable to remove the greater portion of it so that the space in the bell may be primarily available for vapor passed over from the cooling system proper. The dome may be provided with a small vent hole 18 as shown in Figure 6 and preferably is so provided if the bell is relatively large in size. If, however, a relatively small bell is used the designs shown in Figs. 2 to 5 and 8 and 9 may be used without such a top vent.

Depending from the dome '52 of bell 50 is a partition which begins close by the cylindrical wall 42 and then progresses outward in helical convolutions to join the skirt of the bell at 80. It is to be noted that the bottom edge of this partition is lowest where it begins (being lower than the bottom edge of the skirt) and is progressively higher as it curves outward to the skirt of the bell. This helical partition, together with the dome and the surface of the liquid standing within the bell, form a tube-like passageway which winds around and away from the Vertical axis of the bell. As previously stated, the vaporization of the alcohol occurs very irregularly and usually takes place within the water jacket at one or more hot-points of the engine. The vapor passes to the top of the radiator and when enough of it has formed and collected, the resulting pressure (due to the volumetric difference between liquid and vapor) drives the vapor into tube 2! and thence through conduit 38 into the hollow of the cylindrical wall 42. This charge of vapor then passes through the top outlet 62 into the helical passageway.

The eructation of the vapor into the inner or central end of the passageway causes the air to move rapidly along the passageway toward the outer or skirt end and also causes the liquid within the bell to be depressed. This occurs with appreciable rapidity with the result that as the air is forced to the outer end of the passageway, it further depresses the liquid and escapes under the edge of the skirt into the space of the accumulation chamber outside the bell. Thus the bell is substantially cleared of air during this first scavenging of the helical passageway, and the latter is left filled with vapor. But this does not remain as vapor because there is a rapid transfer of heat directly from the vapor to the liquid under it and also indirectly by way of the dome and the depending partition.

The transformation of the vapor back to liquid, with resulting volumetric change, permits the liquid within the bell to rise under the influence of the head of liquid outside the bell. Since the greater portion of the air has been removed as described, the level of the liquid in the bell is higher than before the initial eructation of the vapor and so when vapor is again passed into the bell the liquid therein must be depressed to a greater extent before any of the vapor can escape under the skirt. By selecting a proper size of bell to accommodate the characteristic vaporizing action in the system, the vapor can be retained within the bell between its periods of formation and become condensed in the pauses between the eructations.

In the arrangement of Figures 6 and 7 air within the hell can escape through the restricted vent 18. When such a vented bell is used it is desirable to maintain the liquid level in the accumulation chamber above the dome 52A so that the bell will be filled with liquid. If a large bell is provided with a helical partition as previously described, the vent 78 would preferably be located at the skirt end of the passageway. Upon eructation of vapor into the bell as herespect to the pipe 48.

tofore described, the volume of vapor is so great and the vent 18 is so restricted, that the liquid within the bell is depressed by the vapor which fills the spaces provided between the fins 62 and the dome and skirt of the bell. The rapid transfer of heat from the vapor to the metal dome, its skirt and to the fins promptly effects condensaticn of the vapor caught within the bell. And the small amount of vapor which escapes through the restricted vent l8 enters the cool liquid in the accumulation chamber and is condensed before it can reach the surface of that liquid.

The bell 50B of Figures 8 and 9 is similar in its action to bell 58 of Figures 2 to 5. In this bell the skirt 59B is made in a series of folds to provide narrow spaces radially disposed with re- When the eructation of vapor first occurs it acts with scavenging effect on the air in these narrow vertical spaces, forcing the air and the liquid below it rapidly downward until the greater portion of the air escapes through the notches 54B provided at the lower edge of the skirt.

While it is highly desirable to scavenge the bell of air in order that the -vapor may make contact with the surface of the bell in well-nigh undiluted form, it is also desirable to remove the air so that it will not be drawn back into the radiator upon the cooling of the system. When the engine is stopped and cools down, the solution in the engine jacket and radiator contracts and this tends to form a vacuum at the top of the radiator. As this occurs the atmospheric pressure in the accumulation chamber acting on the liquid therein forces the solution into the conduit 38 and thence through tube 20 back into the radiator. If any air remains entrapped under the dome it might be drawn over into the radiator except for a further provision of the invention which insures that the liquid solution alone will be returned to the radiator until the supply in the accumulation chamber is substantially exhausted. This provision is an orifice 8| in the fluid connection between the accumulation chamber and the radiator. This orifice is below the outlet of the said connection and of sufficient size to accommodate the return flow of the liquid solution. This flow is seldom very rapid since it is eifected by the gradual cooling down of the solution and the consequent tendency to form a vacuum. The orifice thus insures the withdrawal of liquid from the accumulation chamber into the connection 38 and thence into the radiator, rather than any air. Thus the cooling system proper is automatically replenished with the cooling solution and the addition of plain water by an observant garage man or filling station attendant is avoided.

A feature of the apparatus disclosed is the provision of amply large passages for the travel of the liquid and the vapor. The conduit 38 is as large, indeed may be even larger, than the overflow tube 26. The outlet into the bell is as large as the conduit 38 and the space within the bell is relatively of unlimited extent being automatically enlarged as it were by the depression of liquid therein. This feature prevents any clogging or backing up and offers no impediment to the free travel of the vapor or liquid from the radiator to the casing.

In the event of some unusual heating up of the engine, resulting in a condition generally described as steaming, the condenser will of course be taxed beyond its intended capacity.

But provision is made for such an abnormal situation and a free vent provided for the steam through the pipes 14 and 16. This passage is always open and in the event of vapor entering the casing faster than it can be condensed, the excess bubbles to the top of the casing and escapes via the said pipes.

In the event of an unexpected low temperature, so low that the solution normally standing in the lower portion of conduit 38 might become frozen, the subsequent starting of the engine fol lowed by the expansion of the solution in the water jacket and radiator can do no harm, even though its passage to the accumulation chamber is cut off. Safety against this extreme hazard is provided by a simple safety valve which consists of nothing more than a hole 82 or two in the upper end of conduit 38 close by the overflow tube at. These holes are covered by a rubber sleeve 84 (see Figures 10 and 11) which fits snugly around the conduit 38 and normally prevents any escape of liquid or vapor through the holes. But if the lower portion of the conduit should be frozen tight, the liquid tending to fiow into this conduit from the overflow tube 20 causes the rubber sleeve to rupture permitting the liquid to escape through the holes 82. This most unusual escape of the solution would attract attention and lead to a thawing out of the conduit, replacing the ruptured sleeve and a reestablishment of the system to its customary operating condition.

The apparatus is appreciably simple. No check valves, springs or other mechanically acting elements are present. Its addition to the ordinary cooling system of an internal combustion engine can be made with little cost and with little effort. Once installed it permits the use of the much desired alcohol as the anti-freeze agent and insures that under normal operating conditions the solution established as effective for the temperatures expected to be encountered will continue effective and practically unchanged in amount throughout the colder season. The same is equally true if other non-evaporating anti-freeze solutions are used. They will be retained in the system without loss and without danger of their dilution by the addition of any water to fill the radiator.

I claim:

1. Condensing means for the cooling system of an internal combustion engine, comprising a casing having a fluid transmitting connection with the upper portion of said system; and a bell in the casing having a dome and skirt overlying the outlet of said connection with the mouth of said bell so positioned as to be sealed by liquid collecting in said casing.

2. Condensing means for the cooling system of an internal combustion engine, comprising a casing having a fluid transmitting connection with the upper portion of said system; a bell in the casing having a dome and skirt overlying the outlet of said connection with the mouth of said bell so positioned as to be sealed by liquid collecting in said casing; and means within said bell for transfer of heat to said collected liquid from vapor entering the bell.

3. Condensing means for the cooling system of an internal combustion engine, comprising 9. cas. ing openly vented near the top to atmosphere and having at a lower level a fluid transmitting connection with the upper part of the said system; a bell mounted in said casing with its dome and skirt above the outlet of said connection with the mouth of said bell so positioned as to be normally sealed by liquid condensate collecting in said casing; the said bell having a partition therein providing a passageway from said outlet to the skirt of the bell whereby vapor entering the bell through the said outlet forces air in said passageway to escape through said liquid under the skirt of said bell.

4. Condensing means for the cooling system of an internal combustion engine, comprising a casing having a fluid transmitting connection with the upper portion of said system; a bell in the casing having a dome and skirt overlying the outlet of said connection with the mouth of the bell so positioned as to be normally sealed by liquid condensate collecting in said casing; the said outlet being centrally of the bell and there being a helical partition depending from the dome of the bell and extending from close by said inlet to the skirt of the bell to define a spiral passageway.

5. Condensing means for the cooling system of an internal combustion engine, comprising a casing having a, connection with the upper part of said system for transmission of liquid and vapor therefrom; a bell mounted in said casing with its dome and skirt overlying the outlet of said connection with the mouth of the bell so positioned as to be sealed by liquid condensate coilecting in said casing; the internal space defined by said bell and the sealing liquid being of capacity to entrap the vapor transmitted from said system and to retain the vapor between periods of vaporization in the system, whereby heat is transferred from the entrapped vapor to efieot condensation thereof.

6. Condensing means for the cooling system of an internal combustion engine, comprising a casing having a fluid transmitting connection with the upper portion of said system; a bell in the casing having a dome and skirt overlying the outlet of said connection with the mouth of the bell so positioned as to be sealed by liquid condensate collecting in said casing; the said bell having a helical partition depending from its dome into the said liquid and extending from close by the said outlet to the skirt of the bell 5 with the vertical extent of said partition decreasing as it approaches the skirt.

7. Condensing means for the cooling system of an internal combustion engine, comprising a casing having a fluid transmitting connection with the upper portion of said system; a bell in the casing having a dome and skirt overlying the outlet of said connection with the mouth of the bell so positioned as to be sealed by liquid condensate collecting in said casing; and a restricted vent in the upper part of said bell.

8. Condensing means for the cooling system of an internal combustion engine, comprising a casing having a fluid transmitting connection with the upper portion of said system; a bell in the casing having a dome and skirt overlying the outlet of said connection with the mouth of the bell so positioned as to be sealed. by liquid condensate collecting in said casing; there being an orifice in the said connection below said outlet 5 whereby liquid in the accumulation chamber can drain into said connection.

9. Condensing means for the cooling system of an internal combustion engine comprising a casing having a fluid transmitting connection with the upper portion of said system; a bell in the casing having a portion overlying the outlet of said connection and having depending portions positioned to be sealed by liquid condensate collecting in said casing; the bell being shaped to define a passageway from said outlet to a region remote therefrom with the edges of the depending portions at said remote region being at a higher elevation than the remaining edges of said depending portions.

ROBERT S. WENTWORTH. 

